Thermal Performance of Borehole Heat Exchangers
نویسنده
چکیده
An important issue in the design of systems using borehole heat exchangers is to find costeffective methods to construct the borehole heat exchanger so that heat can be injected or extracted from the ground without excessive temperature differences between the heat carrier fluid and the surrounding ground. This paper presents an overview of experiences and current activities in this field.
منابع مشابه
Improvement in Modeling of Heat Transfer in Vertical Ground Heat Exchangers
The heat transfer model of vertical ground heat exchangers for ground-source heat pump systems is discussed. An explicit solution of a finite line-source model has been derived to better describe temperature response of boreholes for long time steps, which can be easily incorporated into computer programs for thermal analysis of ground heat exchangers. A quasi-three-dimensional model is also pr...
متن کاملThermal Efficiency Comparison of Borehole Heat Exchangers with Different Drillhole Diameters
Thermal efficiency of borehole heat exchangers (BHE) is of crucial importance for the design and optimization of ground source heat pump (GSHP) system. This paper investigates thermal efficiency of a BHE with three drillhole diameters: 121 mm, 165 mm and 180 mm. The BHE was installed in a GSHP system of an office building located in Nuremberg, Germany. Thermal properties and hydraulic propertie...
متن کاملModelling and Simulation of Groundwater Influence on Borehole Thermal Energy Stores
Borehole thermal energy stores used for seasonal heat storage in solar assisted district heating systems are very sensitive to groundwater flow. A heat and mass transport model has been developed by the authors in order to simulate the influence of moving groundwater on borehole thermal energy stores. This was done by combining an advanced numerical strategy, where the borehole heat exchangers ...
متن کاملThermal Design Considerations and Performance Evaluation of Cryogenic Tube in Tube Heat Exchangers
Heat exchangers are the most important equipment in refrigeration processes. Design and modeling of heat exchangers operating at low temperatures are different from other regular heat exchangers. This study includes two sections. In the first section, design and modeling considerations needed for evaluating the real thermal behavior of heat exchangers at low temperatures were discussed. The...
متن کاملImprovement Of Thermal Conductivity Of Grout Mixture For Geothermal Heat Pump Systems
A vertical geothermal probe consists of two or four polyethylene tubes U-shaped, used for circulating the coolant between the heat pump and the ground. It is installed in a deep borehole and sealed in a special grout, a kind of liquid cement, used to seal the borehole, and avoid the presence of air bags between the probe and the ground. Moreover, the grout provides a heat transfer medium betwee...
متن کامل